1. Course Overview
What is AI?
What are the Major Challenges?
What are the Main Techniques?
Where are we failing, and why?
Step back and look at the Science
Step back and look at the History of AI
What are the Major Schools of Thought?
What of the Future?
Part I: Introduce you to what’s happening in Artificial Intelligence
Done
Part II: Give you an appreciation for the big picture
 Why it is a grand challenge
What are we trying to do
How do we do it
A lot of people would start with the history – but it’s a bit meaningless at first

2. Done Course Overview Step back and look at the Science
What is AI?
What are the Major Challenges?
What are the Main Techniques?
Where are we failing, and why?
Step back and look at the Science
Step back and look at the History of AI
What are the Major Schools of Thought?
What of the Future?
Part I: Introduce you to what’s happening in Artificial Intelligence
Done
Part II: Give you an appreciation for the big picture
 Why it is a grand challenge
What are we trying to do
How do we do it
A lot of people would start with the history – but it’s a bit meaningless at first

3. Course Overview Looking at the Science
What is AI?
What are the Major Challenges?
What are the Main Techniques?
Where are we failing, and why?
Step back and look at the Science
Step back and look at the History of AI
What are the Major Schools of Thought?
What of the Future?
Looking at the Science
Engineering vs. Science
Introduction to Cognitive Science
Cognitive Psychology 1
Cognitive Psychology 2
Cognitive Development
Linguistics
Neuroscience
Philosophy
What are we trying to do
How do we do it
A lot of people would start with the history – but it’s a bit meaningless at first

4. Course Overview Looking at the Science
What is AI?
What are the Major Challenges?
What are the Main Techniques?
Where are we failing, and why?
Step back and look at the Science
Step back and look at the History of AI
What are the Major Schools of Thought?
What of the Future?
Looking at the Science
Engineering vs. Science
Introduction to Cognitive Science
Cognitive Psychology 1
Cognitive Psychology 2
Cognitive Development
Linguistics
Neuroscience
Philosophy
What are we trying to do
How do we do it
A lot of people would start with the history – but it’s a bit meaningless at first

5. Linguistics in Cognitive Science
Why are Cognitive Scientists Interested in Linguistics?
Language seems to be uniquely human trait
All normal humans use language
Animals don’t seem to
Sometimes have some signals, but no complex grammar, relationships
Not sure about dolphins…
Language is how we express our thoughts
It must give us some hints about those thoughts themselves
Language is easy to study
Compare with brain scans, or anthropology

6. Linguistics in Cognitive Science
Example: Grammar
Grammar is the study of the rules governing the use of a given natural language
Why is that interesting?
Trying to get some scientific hypothesis about the language knowledge native speakers have
How to describe that knowledge?
The dog irritated Mary.
Mary irritated the dog .
Dog the Mary irritated.
Irritated the Mary dog.
Describe grammar as a list of options?
It seems we would have to describe too many options
These rules seem to be best described by algorithms
Quite advanced - recursion
Quite complicated
Note: these are used by ALL speakers, not just some advanced experts

7. Knowledge of Grammar is Implicit
We all know the rules…
but are usually unaware of this knowledge
Everybody knows the rules, but few can write them down
These rules are complicated…
but most kids have learnt most by 5 yrs … how?
Language acquisition – address later

8. Overview of Linguistics Areas
Phonology - sounds
Lexical - words
Morphology - words built up of bits
Syntax – order of words
Semantics - meaning
Words
Sentences
Pragmatics
Pretty much everything else
Example: Context
Example: Gricean maxims
Example: Dialogues

9. Morphology Two types of languages:
Synthetic: stick parts together to make words
English has synthetic features: Unbreakable, Antidisestablishmentarianism
Turkish: Avustralyalılaştıramadıklarımızdanmışsınız
Analytic: order of words is used to make up the meaning
Chinese, many far-eastern languages
Example: tense is indicated by words around, rather than conjugation
Morphemes are smallest bits of language that have meaning
Example: cat, dog, happy, un-, -ness, -s, break, -able, -ory, -ment
Many ways to things
Can compound words: toothbrush
Output of one can input to another
Toothbrush-holder
Unmicrowaveability
Can use recursion
Anti-missile missile
Anti-anti-missile missile missile
Anti-anti-anti-missile missile missile missile
Need to keep track of antis and missiles

10. Phonology
Phonology tells us how words (made of morphemes) get pronounced
Examples…
Plural: cat  cats
Plural: dog  dogs
Pronounced “dogz” … why?
Plural: glass  glasses
What about non-words
Blort  ?
Blorb  ?
Blorch  ?
There seem to be some rules being applied

11. Phonology Example: Do you want to?
Do you wanto
Do you wanna
Dyu wanna
Juwanna
Is this simply what happens when you try to force your voice to go fast
Or are there also rules?
Another example
I’m going to leave (“to” is part of the verb)
I’m gonna leave
I’m going to New York (“to” is a preposition)
I’m gonna New York (sounds odd?)
I’m going to split
I’m going to Split (city in Croatia)
I’m gonna split
Depends on grammar rules…
Interestingly… principles of phonology also apply to sign language
Something common underlying both grammars

12. Syntax Noam Chomsky “A Review of BF Skinner's Verbal Behaviour”
Challenged the behaviourist approach (was dominant in the 1950s)
Especially to the study of language
Sparked the “cognitive revolution” in psychology
Mind contains mental states, beliefs, desires, intentions
Most properties of language and mind are innate (puts him at odds with Piaget)

13. Poverty of the stimulus
Premises:
Patterns in grammar of natural language cannot be learned using positive evidence alone
Children are only ever presented with positive evidence
Children do learn the correct grammars for their native languages
Conclusion
Humans must have some innate knowledge of the rules for language
Example of what is learned:
Statement: You are happy.
Question: Are you happy?
Statement: Anyone who is interested can see me later.
1. Is anyone who interested can see me later?
2. Can anyone who is interested see me later?
Some controversy… some premises not accepted by some
Example: Maybe domain general learning theory adequate
Example: Some say positive evidence is enough

14. Universal Grammar
A basic grammatical structure common to all human languages
Humans are born with innate knowledge of this
Principles and Parameters approach
Grammatical principles underlying languages are innate and fixed
Differences among world's languages are parameter settings in the brain
Example: “pro-drop parameter”
Indicates if an explicit subject is always required
Yes in English
No in Spanish, Maltese
Mar. Maltese sentence "he went/left" (verb)
A child learning a language only needs to
acquire lexical items (words, grammatical morphemes, and idioms)
and determine the appropriate parameter settings
can be done based on a few key examples

15. Universal Grammar Principles and Parameters approach Explains a lot…
Rate at which children learn languages is very fast
Similar learning steps taken by children across the world
Children make same characteristic errors on first language
Some seemingly logical kinds of errors never occur

16. Ambiguity and Garden Paths…
“Rumour had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.”
Human must make choices… how long to entertain alternatives?
“The man who hunts ducks …

17. Ambiguity and Garden Paths…
“Rumour had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.”
Human must make choices… how long to entertain alternatives?
“The man who hunts ducks out on weekends.”

18. Ambiguity and Garden Paths…
“Rumour had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.”
Human must make choices… how long to entertain alternatives?
“The man who hunts ducks out on weekends.”
“Fat people eat …

19. Ambiguity and Garden Paths…
“Rumour had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.”
Human must make choices… how long to entertain alternatives?
“The man who hunts ducks out on weekends.”
“Fat people eat accumulates.”

20. Ambiguity and Garden Paths…
“Rumour had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.”
Human must make choices… how long to entertain alternatives?
“The man who hunts ducks out on weekends.”
“Fat people eat accumulates.”
“The cotton clothing is usually made of …

21. Ambiguity and Garden Paths…
“Rumour had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.”
Human must make choices… how long to entertain alternatives?
“The man who hunts ducks out on weekends.”
“Fat people eat accumulates.”
“The cotton clothing is usually made of grows in Mississippi.”

22. Ambiguity and Garden Paths…
“Rumour had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.”
Human must make choices… how long to entertain alternatives?
“The man who hunts ducks out on weekends.”
“Fat people eat accumulates.”
“The cotton clothing is usually made of grows in Mississippi.”
“The horse raced past the barn …

23. Ambiguity and Garden Paths…
“Rumour had it that, for years, the government building had been plagued with problems. The man was not surprised when he found several spiders, roaches, and other bugs in the corner of his room.”
Human must make choices… how long to entertain alternatives?
“The man who hunts ducks out on weekends.”
“Fat people eat accumulates.”
“The cotton clothing is usually made of grows in Mississippi.”
“The horse raced past the barn fell.”
Conscious processing of grammar is necessary for difficult writing.

24. Language Acquisition Children learn very quickly
17 year old has about 60,000 words
Must learn about 10 new words a day
6 year old has about 13,000 words
Child learns a new word every two hours
Learning a word is not easy
Know what aspect of situation was referred to
Without having to try the word in many situations
Example: gavagai
Humans tend to chop up the world into the same categories

25. Language Acquisition
Do children have a special device for language learning?
Children learn very quickly and easily
Children become perfect speakers
adults usually learn second language imperfectly
and with great difficulty
Children make mistakes, but not the same ones adults make
Example: Children never misjudge appropriate position of question words
Even on basis of sentences like "I know what John ate."

26. Language Acquisition Hawaiian sugar plantations Sign language
Adults from many countries
Communicated in pidgin
Their children invented a creole
Some controversy about the claims
Sign language
Nicaragua created new schools for the deaf
Younger children invented a new sign language

27. Part 2: On a higher level of concepts and thinking, what does language tell us about what is going on inside?

28. Sapir-Whorf Hypothesis
Language's nature influences the habitual thought of its speakers.
Hopi language
Western languages : the present and future are thought of as "places“
Time is a path linking them
"three days" equivalent to "three apples", or "three kilometres“
Native American languages oriented towards process
Inuit people
Numerous words for snow
Modifies the world view of the Eskimo
Creates a different mode of existence for them
Geoffrey Pullum: "The great Eskimo vocabulary hoax“
Language of the Pirahã tribe of Brazil
Contains three counting words: one, two and many.
Pirahã people have difficulty recounting numbers > 3
Controversy: maybe Pirahã have no need to practice doing so

29. Sapir-Whorf Hypothesis
Strong form of hypothesis: language determines thought
Popular in fiction: Orwell’s 1984 newspeak, e.g. no freedom
Generally not accepted nowadays
But some weaker elements may be present
Different languages categorise the world in different ways
In English:
The dog ran through the forest
The dog ran through the table(!)
In English the table is more thought of as its top
Other languages think of it more as its legs

30. Classifiers and Categories
George Lakoff book: Women, Fire and Dangerous Things
Dyirbal language
I - most animate objects, men
II - women, water, fire, violence, and exceptional animals
III - edible fruit and vegetables
IV - miscellaneous (everything else)

31. Metaphors Argument is war Your claims are indefensible
He attacked every weak point in my argument
His criticisms were right on target
I demolished his argument
I’ve never won an argument with him
You disagree? Okay, shoot.
If you use that strategy he’ll wipe you out.
He shot down all of my arguments.

32. Metaphors Time is a resource You’re wasting my time
This gadget will save you hours
I don’t have the time to give you
How do you spend your time these days?
That flat tire cost me an hour
I’ve invested a lot of time in her
I don’t have enough time to spare for that
You’re running out of time
Do you have much time left?
He’s living on borrowed time
Thank you for your time
I lost a lot of time when I got sick

33. Metaphors The conduit metaphor Examples Ideas are objects
Language expressions are containers
Communication is sending
Examples
It’s hard to get that idea across to him
I gave you that idea
Your reasons came through to us
It’s difficult to put my ideas into words
His words carry little meaning
Your words are hollow
The idea is buried in terribly dense paragraphs

34. Metaphors Up is positive, down is negative He is at the peak of health
He came down with flu
His health is declining
I am on top of the situation
He is at the height of his power
His power rose
He fell from power
The stock is rising
We are at an all-time low

35. Metaphors Personification …inflation is an adversary
Life has cheated me
His religion tells him he cannot drink wine
The Michelson-Morley experiment gave birth to a new physical theory
Cancer finally caught up with him
Inflation has attacked the foundations of our economy
Inflation is eating up our profits
Inflation has robbed me of my savings
Inflation has outwitted the best economic minds in the country
…inflation is an adversary
Declare war on inflation
Call for sacrifices
Install a new chain of command

36. Metaphors
Lakoff’s Thesis: cognition is depends on the linguistic metaphor
We are completely immersed in metaphors
There seems to be no way to say some things without metaphors